I have a 12 year old Aralia whose bottom leaves periodically begin turning yellow and then fall off.The plant is about 6 feet tall now and is beginning to be mostly trunk with leaves only on the top 18 inches.There is a secondary slender trunk branching out from the bottom of the main trunk and now it is getting yellow leaves also. I wondered if it needed magnesium and fed it some epsom salts and the problem disappeared for a few months but now it is back again.I hate to lose the plant as it was a gift from my daughter and I have kept it going for a long time now. I don’t have any photos but if you could help I would appreciate it Thank You, Carole Jackson
Without seeing the plant, I’m going to make a few suggestions and you can see if any pertain to your plant. I am not even certain what variety of Aralia you have. The picture below is a Ming Aralia.
1. The main cause of leaf drop is usually over-watering. Do you cut back on the amount of water you give the plant during the winter months?
2. Aralias like to have their soil changed yearly to prevent the build-up of fertilizerPlants need fertilizer only when they are actively growing. Slow growing plants in low light require very little plant food. Too much fertilizer is worse than not enough. Most plants prefer a water soluble plant food at 1/2 the recommended strength. Plants that are in bloom or dormant should not be fertilized. Houseplant food contains nitrogen (N), phosphorus (P), and potassium (K). A fertilizer containing these elements in equal proportion is considered a balanced plant food. Nitrogen helps in photosynthesis and encourages the growth of leaves and stems. Potassium and phosphorus also help in photosynthesis and aid in root and flower development. Most fertilizers have trace elements of other minerals that are lacking in the soil but are necessary for good plant growth. Fertilizers have a high salt content. If a plant is not producing new leaves and doesn’t absorb the fertilizer, salts build up in the soil. These salts can burn the roots, discolor the leaves, and cause new growth to be small. in the soil that burns the leaves. When did you last change the soil?
3. It sounds like your problem might be seasonal. Do the lighting, heating, or humidity change when the plant starts to drop leaves? Aralias do best in warm, bright, humid areas. Was the light sufficient during the winter months? Did the temperature suddenly drop to 65 degrees? Was the plant in a draft? Did you reduce your watering during the winter months?
4. An Aralia Plant requires very little fertilizer. Feed an Aralia Plant every other month when it’s actively growing with a plant food high in nitrogen at 1/2 the recommended strength.
5. If there are no signs of houseplant pests such as scaleSoft Brown Scale is the most common scale that attacks indoor houseplants especially ficus, ivy, spider plants, ferns, aralia, and schefflera. It appears as small bumpy brown spots that appear to move. As the scale sucks on the sap of the plant it secretes a sticky substance called honeydew. The honeydew attracts black mildew. Because of the shell-like exterior, sprays are only partially effective against scale. Wipe off the lines of brown oval bumps with your finger, a cloth, or a child’s toothbrush then spray the plant with Neem Oil. Use the Green Solution to clean off the black mildew. on the stems or leaves, I think your Aralia leaf loss is probably due to temperature changes.
You can read all about how to care for Aralias in the popular Houseplant section of the website.
Please let me know if none of these causes applies to your plant and I’ll make some more suggestions.